Multi-slot ultra-wideband omnidirectional monopole antenna

Abstract

The invention relates to the technical field of antennas, in particular to a multi-slot ultra-wideband omnidirectional monopole antenna, which comprises a radiation patch, a metal ground, a gradient microstrip line and a dielectric plate, and is characterized in that the radiation patch and the metal ground are respectively arranged on the top surface and the bottom surface of the dielectric plate, and the gradient microstrip line is connected with the radiation patch and an external feed power supply; wherein the upper half part of the radiation patch is provided with a plurality of rectangular grooves, a slender gap and a rotary rectangular groove, and the lower half part of the radiation patch is arranged to be in a symmetrical nine-step shape; the metal ground covers the lower half part of the bottom of the dielectric plate, and the top end of the metal ground is designed into a 1 / 4 arc shape and is provided with two slender rectangular grooves. The gradient microstrip line is connected with the radiation patch and the feed source, and the upper end narrow part is connected with the radiation patch, gradually changes to the lower end wide part and is connected with the feed source through the rectangular patch. Compared with a traditional omnidirectional antenna, the omnidirectional antenna is simple in structure, low in profile, low in manufacturing cost and suitable for rapid printing and manufacturing, and overcomes the defects that an existing omnidirectional antenna is narrow in frequency band, large in out-of-roundness and the like.

Description

Technical Field

[0001] The invention relates to the technical field of antennas, and in particular to a multi-slot ultra-wideband omnidirectional monopole antenna. Background Art

[0002] In modern wireless communication and radar systems, omnidirectional antennas are widely used due to their 360° coverage radiation characteristics, especially in applications that require full signal coverage and avoid antenna direction adjustment. Omnidirectional antennas can provide uniform signal coverage during reception and transmission, and are particularly suitable for environments with significant multipath effects, such as urban high-rise dense areas and complex indoor environments. There are many studies on broadband omnidirectional antennas, mainly including omnidirectional single antenna design and omnidirectional antenna array design. The advantage of omnidirectional single antenna is that the structure is simple and does not require bias circuits and other structures, but the disadvantage is that most of the current omnidirectional single antennas are three-dimensional structures, which are inconvenient to integrate, and the frequency band is not wide, and cannot fully cover the current mainstream communication frequency bands, and the gain within the frequency band is not flat. The advantage of ultra-wideband omnidirectional antenna arrays is that the gain is large, but the frequency band is narrow, the bias circuit has a large impact, and the volume is relatively large.

[0003] Due to the shortcomings of current omnidirectional antennas, such as large non-circularity, relatively narrow bandwidth, and inability to fully cover mainstream communication frequency bands, it is difficult to meet the requirements for applications in various radio frequency communication equipment. Summary of the invention

[0004] The object of the present invention is to provide a multi-slot ultra-wideband omnidirectional monopole antenna that meets the requirements of omnidirectional coverage of the entire frequency band of 1-6G and has the characteristics of simple structure, low profile, wide frequency band and small non-circularity.

[0005] To achieve the above object, the present invention provides a multi-slot ultra-wideband omnidirectional monopole antenna, comprising a radiation patch, a metal ground, a gradient microstrip line and a dielectric plate, wherein the radiation patch is located on the upper layer of the dielectric plate; the metal ground is located below the dielectric plate; the gradient microstrip line is arranged above the dielectric base and is connected to the radiation patch and an external feeding source as a feeding structure in a side-feeding manner;

[0006] The radiation patch has a symmetrical structure, and the overall plane is in an inverted trapezoidal structure that is larger at the top and smaller at the bottom. Nine steps are arranged on each side, and a rectangular frame is opened outside the outermost step.

[0007] Among them, the top of the radiation patch is provided with slender horizontal and vertical slits, and the slender horizontal and vertical slits are orthogonally arranged in the shape of the letter T. There are 4 identical rectangular grooves on both sides of the vertical slit, and rectangular grooves rotated 45° are symmetrically arranged on both sides of the bottom end of the vertical slit. A rectangular groove is also provided at the bottom of the radiation patch.

[0008] The metal ground only covers half of the bottom surface of the dielectric plate, and the two sides of the top of the plane adopt a 1 / 4 arc design with a radius of 9.5 mm, and two slender rectangular grooves are opened in the middle of the top.

[0009] The gradient microstrip line is configured to be narrow at the top and wide at the bottom, the narrow portion at the top is connected to the radiation patch, and the wide portion at the bottom is connected to the feed port / external feed source through a small rectangular patch.

[0010] The present invention provides a multi-slot ultra-wideband omnidirectional monopole antenna, comprising a radiating patch, a metal ground, a gradient microstrip line and a dielectric plate, wherein the radiating patch and the metal ground are respectively arranged on the top and bottom surfaces of the dielectric plate, and the gradient microstrip line connects the radiating patch and an external feed source, wherein the upper half of the radiating patch is provided with a plurality of rectangular slots, slender gaps and rotating rectangular slots, and the lower half is arranged in a symmetrical 9-step ladder shape; the metal ground covers the lower half of the bottom of the dielectric plate, and the top is designed as a 1 / 4 arc shape and has two slender rectangular slots. The gradient microstrip line connects the radiating patch and the feed source, and the narrow part at the upper end is connected to the radiating patch, gradually changes to the wide part at the lower end, and is connected to the feed source through a rectangular patch. It has been verified that the present invention achieves ultra-wideband coverage from 1 GHz to 6 GHz, and the non-circularity of the directional pattern is less than 6 dB in the full frequency band, with low reflection loss. Compared with traditional omnidirectional antennas, it has a simple structure, low profile, low manufacturing cost, and is suitable for rapid printing and manufacturing. It overcomes the shortcomings of existing omnidirectional antennas such as narrow frequency band and large non-circularity. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0012] Figure 1 The present invention is a schematic diagram of a top view of the structure of a multi-slot ultra-wideband omnidirectional monopole antenna.

[0013] Figure 2 The present invention is a schematic diagram of the upward structure of a multi-slot ultra-wideband omnidirectional monopole antenna.

[0014] Figure 3 It is a schematic diagram of top view dimensioning of a multi-slot ultra-wideband omnidirectional monopole antenna of the present invention.

[0015] Figure 4 It is a schematic diagram of dimension annotations of a multi-slot ultra-wideband omnidirectional monopole antenna in an upward view according to the present invention.

[0016] Figure 5It is an S11 parameter diagram of a multi-slot ultra-wideband omnidirectional monopole antenna of the present invention.

[0017] Figure 6 It is the radiation pattern of the H-plane of the multi-slot ultra-wideband omnidirectional monopole antenna at 1 GHz frequency in a specific embodiment of the present invention.

[0018] Figure 7 It is the radiation pattern of the H-plane of the multi-slot ultra-wideband omnidirectional monopole antenna at 2 GHz frequency in a specific embodiment of the present invention.

[0019] Figure 8 It is the radiation pattern of the H-plane of the multi-slot ultra-wideband omnidirectional monopole antenna at 3 GHz frequency in a specific embodiment of the present invention.

[0020] Fig. 9 It is the radiation pattern of the H-plane of the multi-slot ultra-wideband omnidirectional monopole antenna at 4 GHz frequency in a specific embodiment of the present invention.

[0021] Fig.10 It is the radiation pattern of the H-plane of the multi-slot ultra-wideband omnidirectional monopole antenna at 5 GHz frequency in a specific embodiment of the present invention.

[0022] Fig.11 It is the radiation pattern of the H-plane of the multi-slot ultra-wideband omnidirectional monopole antenna at 6 GHz frequency in a specific embodiment of the present invention.

[0023] 1-Radiation patch, 2-Metal ground, 3-Gradient microstrip line, 4-Dielectric board. DETAILED DESCRIPTION

[0024] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0025] See also Figure 1 and Figure 2 The present invention provides a multi-slot ultra-wideband omnidirectional monopole antenna, comprising a radiation patch 1, a metal ground 2, a gradient microstrip line 3 and a dielectric plate 4, wherein the radiation patch 1 is located on the upper layer of the dielectric plate 4; the metal ground 2 is located below the dielectric plate 4; the gradient microstrip line 3 is arranged above the dielectric base and is connected to the radiation patch 1 and an external feeding source as a feeding structure in a side-feeding manner;

[0026] The radiation patch 1 is a symmetrical structure, and the overall plane is an inverted trapezoidal structure that is larger at the top and smaller at the bottom. There are 9 steps on each side, and a rectangular frame is opened outside the outermost step.

[0027] The top of the radiation patch 1 is provided with slender horizontal and vertical slits, which are orthogonally arranged in the shape of the letter T. Four identical rectangular grooves are distributed on both sides of the vertical slit, and rectangular grooves rotated 45° are symmetrically arranged on both sides of the bottom end of the vertical slit. A rectangular groove is also provided at the bottom of the radiation patch 1.

[0028] The metal ground 2 only covers half of the bottom surface of the dielectric plate 4, and the two sides of the top of the plane adopt a 1 / 4 arc design with a radius of 9.5 mm, and two slender rectangular grooves are opened in the middle of the top.

[0029] The gradient microstrip line 3 is configured in a gradient shape with a narrow top and a wide bottom. The narrow top portion is connected to the radiation patch 1, and the wide bottom portion is connected to the feed port / external feed source through a small rectangular patch.

[0030] Specific structural dimensions such as Figure 3 and Figure 4 As shown, the data unit is millimeter.

[0031] The following is further described in conjunction with specific embodiments:

[0032] In this embodiment, the dielectric plate is made of common FR4 (epoxy resin) plate material, with a relative dielectric constant of 4.4, a tangent loss of 0.02, and a thickness of 1.5 mm. The antenna shape is as follows: Figure 1 As shown, the side-feed mode is adopted and the input impedance is 50Ω.

[0033] The radiation patch is arranged above the dielectric substrate with a symmetrical structure, with a center frequency of 3.5 GHz and a length of 43 mm. The lower part adopts a nine-step layout to extend the current path and widen its impedance bandwidth. The rectangular slot at the bottom is 3.5 mm away from the bottom, and the four identical rectangular slots at the top are distributed on both sides, 4.5 mm away from the top. A slotted step protrudes from each side, and a 0.5 mm wide slender horizontal and vertical slot and a 1 mm wide vertical slot are set in the middle of the top to cut off the lateral current and improve the omnidirectional radiation characteristics near the 6G frequency point. There is a rectangular slot rotated 45° on the left and right sides of the middle, and the bottom is connected to the gradient microstrip line.

[0034] The metal ground is arranged under the dielectric substrate with a length of 44.25mm. The top sides adopt a 1 / 4 arc design with a radius of 9.5mm, which helps to miniaturize the floor and improve the omnidirectional radiation characteristics near the 1G frequency point. There are two slender rectangular grooves in the middle of the top, with widths of 0.3mm and 0.45mm from top to bottom, which are used to adjust the impedance matching so that the impedance bandwidth is continuous throughout the frequency band. The bottom is connected to the feeding port.

[0035] The gradient microstrip line is arranged above the dielectric substrate, with the narrow part at the top connected to the radiation patch, and the wide part at the bottom connected to the feed port through a small rectangular patch. Its width gradually changes from 1.53mm at the top to 3.44mm at the bottom. Its gradient structure makes the impedance change gradually, achieving impedance matching in the entire frequency band.

[0036] Further, the present invention provides a performance description of antenna parameters, please refer to Figures 5 to 11 .

[0037] Figure 5 2 shows the reflection coefficient curve of the multi-slot ultra-wideband omnidirectional monopole antenna of the present invention. The S11 of the antenna is significantly less than -10dB in the frequency range of 0.93-7.3GHz, and no cut-off phenomenon occurs.

[0038] Figures 6 to 11 The figure shows the radiation pattern of the H-plane of the ultra-wideband omnidirectional monopole antenna.

[0039] In summary, compared with the prior art, the present invention has the following advantages:

[0040] a) Large impedance bandwidth, which can achieve ultra-wideband of 1-6GHz, covering most communication frequency bands;

[0041] b) Small non-circularity: in the full frequency band of 1-6GHz, the non-circularity of the radiation pattern is less than 6dB;

[0042] c) Simple structure and easy manufacturing. Compared with omnidirectional antenna arrays, the design structure is simple and the planar microstrip structure can be quickly printed and manufactured.

[0043] What is disclosed above is only a preferred embodiment of the present invention, and it certainly cannot be used to limit the scope of rights of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above embodiment and equivalent changes made according to the claims of the present invention still fall within the scope of the invention.

Claims

1. A multi-slot ultra-wideband omnidirectional monopole antenna, characterized in that: It includes a radiation patch, a metal ground, a gradient microstrip line and a dielectric plate, wherein the radiation patch is located on the upper layer of the dielectric plate; the metal ground is located below the dielectric plate; the gradient microstrip line is arranged above the dielectric base and is connected to the radiation patch and an external feed source as a feeding structure in a side-feeding manner; The radiation patch has a symmetrical structure, and the overall plane is in an inverted trapezoidal structure that is larger at the top and smaller at the bottom. Nine steps are arranged on each side, and a rectangular frame is opened outside the outermost step.

2. The multi-slot ultra-wideband omnidirectional monopole antenna according to claim 1, characterized in that: The top of the radiation patch is provided with slender horizontal and vertical slits, which are orthogonally arranged in the shape of the letter T. Four identical rectangular grooves are distributed on both sides of the vertical slit, and rectangular grooves rotated 45° are symmetrically arranged on both sides of the bottom end of the vertical slit. A rectangular groove is also provided at the bottom of the radiation patch.

3. The multi-slot ultra-wideband omnidirectional monopole antenna according to claim 2, characterized in that: The metal ground only covers half of the bottom surface of the dielectric plate, and both sides of the top of the plane adopt a 1 / 4 arc design with a radius of 9.5 mm, and two slender rectangular grooves are opened in the middle of the top.

4. The multi-slot ultra-wideband omnidirectional monopole antenna according to claim 3, characterized in that: The gradient microstrip line is arranged in a gradient shape with narrow upper part and wide lower part, the narrow part at the top is connected to the radiation patch, and the wide part at the bottom is connected to the feeding port / external feeding source through a small rectangular patch.

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